Controlling ultraviolet intensity over a surface of a light sensitive object

Abstract

An approach for controlling ultraviolet intensity over a surface of a light sensitive object is described. Aspects involve using ultraviolet radiation with a wavelength range that includes ultraviolet-A and ultraviolet-B radiation to irradiate the surface. Light sensors measure light intensity at the surface, wherein each sensor measures light intensity in a wavelength range that corresponds to a wavelength range emitted from at least one of the sources. A controller controls the light intensity over the surface by adjusting the power of the sources as a function of the light intensity measurements. The controller uses the light intensity measurements to determine whether each source is illuminating the surface with an intensity that is within an acceptable variation with a predetermined intensity value targeted for the surface. The controller adjusts the power of the sources as a function of the variation to ensure an optimal distribution of light intensity over the surface.

What is claimed is: 
     
       1. A lighting system, comprising:
 an array of ultraviolet radiation sources configured to irradiate a surface of a light sensitive object with ultraviolet radiation having a wavelength range that includes ultraviolet-A (UV-A) radiation, ultraviolet-B (UV-B) radiation and blue-ultraviolet (blue-UV) radiation, wherein each of the ultraviolet radiation sources irradiates the surface of the object at a target radiation over a predetermined wavelength range, at least one of the ultraviolet radiation sources operates at a peak wavelength that is within a UV-B wavelength range, and wherein at least one of the ultraviolet radiation sources operates at a peak wavelength that is within at least one of the UV-A wavelength range or the blue-UV wavelength range; 
 a plurality of light sensors configured to measure light intensity at the surface of the object, wherein each light sensor measures light intensity in a wavelength range that corresponds to the predetermined wavelength range emitted from one of the ultraviolet radiation sources in the array; and 
 a controller configured to control the light intensity over the surface of the object as a function of light intensity measurements obtained from the light sensors, wherein the controller uses the light intensity measurements to determine whether each ultraviolet radiation source is illuminating the surface of the object at a dose that delivers the ultraviolet radiation at an intensity that is within an acceptable variation with a predetermined light intensity value, the controller adjusting the power of an ultraviolet radiation source in response to determining that the ultraviolet radiation source is illuminating the surface with an intensity that has an unacceptable variation with the predetermined light intensity value targeted for the surface, each ultraviolet radiation source that is adjusted in power delivers an adjusted dose of the ultraviolet radiation that is a function of an amount of the unacceptable variation with the predetermined light intensity value. 
 
     
     
       2. The lighting system of  claim 1 , wherein the acceptable variation with the predetermined intensity value is at most 5%. 
     
     
       3. The lighting system of  claim 1 , wherein the dose is in the range of 0.1 kJ/m 2  to 20 kJ/m 2 . 
     
     
       4. The lighting system of  claim 1 , wherein each of the ultraviolet radiation sources in the array delivers ultraviolet radiation to the surface of the object in short pulses. 
     
     
       5. The lighting system of  claim 4 , wherein each pulse of ultraviolet radiation generated from an ultraviolet radiation source is less than an amount of time needed for achieving a steady state temperature of operating the ultraviolet radiation source. 
     
     
       6. The lighting system of  claim 1 , wherein the array of ultraviolet radiation sources is configured for movement about the object, wherein the movement includes both translational and directional degrees of freedom. 
     
     
       7. The lighting system of  claim 1 , wherein the array of ultraviolet radiation sources irradiates the surface of the object for a predetermined duration that is no more than six hours per day. 
     
     
       8. The lighting system of  claim 1 , wherein the array of ultraviolet radiation sources includes a greater amount of ultraviolet radiation sources located at side portions of the array in comparison to an amount of ultraviolet radiation sources located near a central region of the array, wherein the side portions include at least 10% more ultraviolet radiation sources than the amount of ultraviolet radiation sources located near the central region. 
     
     
       9. The lighting system of  claim 8 , wherein the ultraviolet radiation sources located at the side portions of the array operate at a higher pulsed frequency than the ultraviolet radiation sources located near the central region. 
     
     
       10. The lighting system of  claim 8 , wherein the ultraviolet radiation sources located at the side portions of the array operate at a higher power than the ultraviolet radiation sources located near the central region. 
     
     
       11. The lighting system of  claim 1 , further comprising a plurality of fluorescent sources to irradiate the surface of the object in conjunction with the ultraviolet radiation sources. 
     
     
       12. The lighting system of  claim 11 , further comprising a plurality of fluorescent sensors to detect fluorescent radiation reflected from the surface of the object, wherein the fluorescent sources and the fluorescent sensors operate in a pulsed regime to differentiate from fluorescent signals reflected from the surface that arise from the irradiation by the ultraviolet radiation sources. 
     
     
       13. The light sensing system of  claim 1 , wherein at least one of the light sensors comprises a visible camera. 
     
     
       14. A lighting system, comprising:
 an array of ultraviolet radiation sources configured to irradiate a surface of a light sensitive surface object with ultraviolet radiation, wherein the ultraviolet radiation sources can operate in a predetermined wavelength that includes at least one of: a UV-A radiation wavelength range or a UV-B radiation wavelength range, wherein at least one of the ultraviolet radiation sources can operate at a peak wavelength that is within a wavelength range from 315 nm to 400 nm; 
 a light sensor configured to measure light intensity at the surface of the object, wherein the light sensor measures light intensity in a wavelength range that corresponds to the predetermined wavelength range emitted from at least one of the ultraviolet radiation sources in the array; and 
 a controller configured to detect a change in the object by using data feedback from the light sensor and control the light intensity over the surface of the object, wherein the controller receives light intensity signals from the light sensor and determines whether the light intensity at the surface of the object exceeds an acceptable variation with a predetermined intensity value, 
 the controller adjusting the power of an ultraviolet radiation source in response to determining that the light intensity at the surface of the object exceeds the acceptable variation with the predetermined intensity value, 
 each ultraviolet radiation source that is adjusted in power delivers an adjusted dose of the ultraviolet radiation that is a function of an amount of an unacceptable variation with the predetermined light intensity value, and 
 wherein the light sensor acquires data corresponding to visible fluorescent radiation from the surface of the object. 
 
     
     
       15. The lighting system of  claim 14 , wherein the ultraviolet radiation sources in the array deliver ultraviolet radiation to the surface of the object in short pulses. 
     
     
       16. The lighting system of  claim 14 , wherein the controller includes an input component and an output component to allow a user to interact with the lighting system and to receive information regarding the surface of the object and the treatment thereto with the ultraviolet radiation sources. 
     
     
       17. The lighting system of  claim 14 , further comprising fluorescent sensors to detect fluorescent radiation reflected from the surface of the object, wherein the fluorescent sensors operate in a pulsed regime to differentiate from fluorescent signals reflected from the surface that arise from the irradiation by the ultraviolet radiation sources. 
     
     
       18. The lighting system of  claim 14 , wherein the array of ultraviolet radiation sources is configured for movement about the object, wherein the movement includes both translational and directional degrees of freedom. 
     
     
       19. The lighting system of  claim 14 , wherein the controller comprises a computer system including an analysis program which makes the computer system operable to manage the ultraviolet radiation sources and the light sensor, wherein the analysis program can enable the computer system to operate the ultraviolet radiation sources to irradiate towards the object, process data obtained during operation, and store the obtained data. 
     
     
       20. A lighting system, comprising:
 a set of ultraviolet radiation sources configured to irradiate a surface of a light sensitive object with ultraviolet radiation with a wavelength range that includes ultraviolet-A (UV-A) radiation and ultraviolet-B (UV-B) radiation, wherein each of the ultraviolet radiation sources operates in a predetermined wavelength range that includes at least one of a UV-A radiation wavelength range or a UV-B radiation wavelength range, wherein at least one of the ultraviolet radiation sources includes a UV-B source configured to operate at a peak wavelength that is within the UV-B wavelength range, and wherein at least one of the ultraviolet radiation sources includes a UV-A source configured to operate at a peak wavelength that is within the UV-A wavelength range; 
 a set of visible light sources configured to irradiate the surface of the object with visible radiation, wherein at least one of the visible light sources includes a blue light source configured to operate within a blue light wavelength range; 
 a plurality of light sensors configured to measure light intensity at the surface of the object, wherein each light sensor measures light intensity in a wavelength range that corresponds to the range of wavelengths emitted from at least one of the set of ultraviolet radiation sources or the set of visible light sources; and 
 a controller configured to control the irradiation of the object by the set of ultraviolet radiation sources and the set of visible light sources, wherein the controller directs the UV-B source and at least one of the UV-A source or the blue light source to irradiate the object at a corresponding radiation, wherein the controller controls the light intensity over the surface of the object by adjusting operational power of the ultraviolet radiation sources and the visible light sources as a function of light intensity measurements obtained by the light sensors, the controller using the light intensity measurements to determine whether each ultraviolet radiation source is illuminating the surface of the object with an intensity that has a variation that is more than 50% of a predetermined intensity value targeted for the surface, the controller adjusting the power of an ultraviolet radiation source and/or a visible light source in response to determining that the ultraviolet radiation source and/or the visible light source is illuminating the surface of the object with an intensity that has a variation that is more than 50% of the predetermined intensity value targeted for the surface, the controller adjusting the power of an ultraviolet radiation source and/or a visible light source as a function of the variation between the light intensity generated from the source and the predetermined intensity value targeted for the surface.